I can agree with Duncan's basic premise that the torque tube is
equally strong in both directions, and let's assume ditto for strength
of the fuselage. The ultimate question is how much strength that is.
Whatever load is on the tail while pulling +3.8G's, when deflected in
the opposite direction at equal loading on the tail, will place twice
the load limit of -1.9G on the wings. Actually more, since the plane
is nose heavy if loaded within CG limits, so the tail doesn't have to
work as hard in negative G's. So looks to me, theoretically the wings
should break before the tail does.
Best,
Fred F.
> Duncan
>
> Your symmetrical loading theory is probably erroneous. The stabilator is
> normally loaded downward (negative lift) when it is in a neutral position.
> Therefore, it will take less downward deflection to reach the critical
> (breaking) point. Upward deflection (12 degrees) gets to overcome the
> downward
> loading before it even starts to give positive lift loads as it deflects
> upward.
>
> Regards
>
> Tom Friedland A079
>
> McFadyean wrote:
>
> > All true. Only the structure of the tailplane and its support is
> > symmetrical in a vertical plane. So if it will take 12 degrees or so in the
> > "up" direction then it should take similarly in the "down" direction.
> >
> > Duncan McFadyean
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